This invention relates generally to connecting rods for internal combustion engines, and more particularly to a connecting rod whose length will vary to increase the degree of compression of the combustible fuel-air mixture in the cylinder of the engine under low or closed throttle operating conditions.
It is well-known that present day, four cycle internal combustion engines burn and utilize fuel more efficiently under full or open throttle conditions than under low or closed throttle conditions. This is because a partially closed throttle restricts the inflow of combustion air into the fuel intake manifold and/or the cylinder of the engine, so that the influent fuel-air charge is at a lower pressure and density than an influent fuel-air charge inducted into the engine cylinder under a more open throttle condition. Thus, when a relatively low density influent fuel mixture is compressed by the compression stroke of the engine piston, the pressure to which it is subjected at the time of firing is less than the pressure attained with a denser influent mixture.
Failure of the engine to compress the less dense (low throttle) fuel charges to the extent to which the denser (open throttle) fuel charges are compressed results in inefficient operation and consequent fuel wastage and air pollution hazards.